High File System Page-in Rate

If you are seeing high file system page-in rates on Solaris 8 or 9,
you may benefit from increasing the value of segmap_percent. This parameter is set by adding
the following line to the /etc/system file:

set segmap_percent=25

segmap_percent adjusts the percentage of memory that
the kernel will map into its address space for the file system cache. The
default value is 12; that is, the kernel will reserve enough space to map
at most 12% of memory for the file system cache. On a heavily loaded machine
with 4 GB of physical memory, improvements have been seen with values as high
as 60. You should experiment with this value, starting with values around
25. On systems with large amounts of physical memory, you should raise this
value in small increments, as it can significantly increase kernel memory
requirements.